forced-colors-mode/forced-colors-mode-17.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Forced colors mode - text decoration and emphasis color.</title>
<link rel="help" href="https://www.w3.org/TR/css-color-adjust-1/#forced-colors-properties">
<link rel=match href="forced-colors-mode-17-ref.html">
<style>
  p {
    text-decoration: underline;
    text-decoration-color: red;
    text-emphasis: '*' blue;
    -webkit-text-emphasis: '*' blue;
  }
</style>
<body>
  <p>
    The text decoration and emphasis color for this text should have a
    CanvasText color in forced colors mode.
  </p>
</body>